SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = 'ae88e9ee51a01b80ef519fa235640b38a352b0aac524e240d8943d8a30675e32' 
  AND token = 'gUQhbm5iYCBhkkKR97oWcBXhKQLVjmwAODEm9NA0y7o=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00025

JSON explain

{
  "query_block": {
    "select_id": 1,
    "message": "no matching row in const table"
  }
}